UPDATED 24th October using data parsed 20th October
The update this time uses a larger data set and also includes a normalised version for each bracket using the Warcraft Census Data. I do not know how accurate the census data is however.
Some very interesting results in the normalised versions, e.g. taking into account population the Mage actually underperforms in all 3 brackets and the Warrior is far less of a dominating force.
Realms: All 107 eu.armory realms
Teams: 127,953 (14,298 ignored with 0 games played)
Make of it what you will. :)